Correlation between the mean matter density and the width of the saturated Lyα absorption

  title={Correlation between the mean matter density and the width of the saturated Ly$\alpha$ absorption},
  author={Hu Zhan},
  journal={Monthly Notices of the Royal Astronomical Society},
  • H. Zhan
  • Published 24 May 2003
  • Physics
  • Monthly Notices of the Royal Astronomical Society
We report a scaling of the mean matter density with the width of the saturated Lya absorptions. This property is established using the 'pseudo-hydro' technique (Croft et al.). It provides a constraint for the inversion ofthe Lya forest, which encounters difficulty in the saturated region. With a Gaussian density profile and the scaling relation, a simple inversion of the simulated Lya forests shows that the one-dimensional mass power spectrum is well recovered on scales above 2 h - 1 Mpc, or… 

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